Describing the alcohol harm paradox: 20 years of data from Victoria, Australia.

Background and aims: Internationally, rates of harm from alcohol tend to be higher in lower socio-economic groups, even while drinking is lower. This is known as the alcohol harm paradox. There are very little Australian data published on socio-economic disparities in alcohol consumption and harm, and none that has examined changes over time. This paper aimed to describe trends in socio-economic inequalities in key measures of alcohol consumption and alcohol-related harm over 21 years in Victoria, Australia.

Design: Trend analysis of population rates of separate data on hospital, emergency department and drinking behaviour.

Setting: Victoria, Australia, between 2000 and 2020.

Participants/cases: Survey data from 37 422 respondents plus 841 792 hospital admissions and 591 824 emergency department presentations.

Measurements: Socio-economic status was measured using an area-based index based on postcode of residence, divided into quintiles. Two measures of drinking were assessed based on survey responses: annual volume of drinking and frequency of risky (50 g or more) drinking occasions. Chronic harms were measured via hospital admissions for alcohol-related liver disease and acute harms via emergency department presentations for alcohol-related disorders. Differences in drinking and harm rates across quintiles were assessed using negative binomial regression, with interactions to examine whether the social gradients changed over time.

Findings: For men, there were no statistically significant differences in either total volume of drinking or frequency of episodic risky drinking between socio-economic quintiles. For women, volume of drinking was generally higher for those living in more advantaged neighbourhoods [e.g. Incident Rate Ratio (IRR) = 1.60, 95% confidence interval (CI) = 1.32-1.95 for women in the most advantaged compared with most disadvantaged], while frequency of episodic risky drinking did not differ statistically significantly. Trends in drinking on either measure did not differ by socio-economic status for men or women. Alcohol-related harms were higher for people living in disadvantaged neighbourhoods for most outcomes and sub-groups analysed. For example, male rates of alcohol-related liver disease were nearly twice as high in the most disadvantaged quintile as in the least disadvantaged quintile (IRR = 0.54, CI = 0.50-0.58). On some measures there was evidence that the gap between socio-economic groups had widened over time.

Conclusions: Despite similar or lower levels of alcohol consumption, people living in more disadvantaged socio-economic areas of Victoria, Australia, appear to experience much higher rates of alcohol-related harm than those in more advantaged areas, with some disparities widening over time.